12400505 has 16 divisors (see below), whose sum is σ = 16257024. Its totient is φ = 9024960.

The previous prime is 12400489. The next prime is 12400511. The reversal of 12400505 is 50500421.

It is not a de Polignac number, because 12400505 - 2⁴ = 12400489 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3272 + ... + 5958.

It is an arithmetic number, because the mean of its divisors is an integer number (1016064).

Almost surely, 2^12400505 is an apocalyptic number.

It is an amenable number.

12400505 is a deficient number, since it is larger than the sum of its proper divisors (3856519).

12400505 is a wasteful number, since it uses less digits than its factorization.

12400505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2776.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 12400505 is about 3521.4350767833. The cubic root of 12400505 is about 231.4620475268.

Adding to 12400505 its reverse (50500421), we get a palindrome (62900926).

The spelling of 12400505 in words is "twelve million, four hundred thousand, five hundred five".